1) (7x+1)-(6x+3) = 5
2) (8x+11)-13=9x-5
3)2=(3x-5)-(7-4x)
4)8x+5 = 119+(7-3x)
5)6x+(3x-2) = 14
6) 8y-(7y-142) = 51
7) 11x+103=1+(12x-31)

7х + 1 - 6х - 3 = 5х = 5 - 1 + 3х = 7---------------------------------8х + 11 - 13 = 9х - 58х - 9х = -11 + 13 - 5-х = - 3х = 3---------------------------------------3х - 5 - 7 + 4х = 27х = 2 + 5 + 77х = 14х = 2----------------------------------8х + 5 = 119 + 7 - 3х8х + 3х = 119 + 7 - 511х = 121х = 11------------------------------------6х + 3х - 2 = 149х = 14 + 29х = 16х = 1целая 7/9------------------------------------------8у - 7у + 142 = 51у = -142 + 51у = - 91----------------------------------------11х + 103 = 1 + 12х - 3111х - 12х = - 103 + 1 - 31- х = -133  х = 133